# Tag Info

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I think I'm in a bit over my head, but I don't think it's convection. The Corona, because of the sun's high gravity, thins out very quickly. http://sunearthday.gsfc.nasa.gov/2008/TTT/58_hotcorona.php from the article: It would be like standing in your kitchen far away from the open oven, but feeling temperatures almost 100 times higher than ...

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You've actually identified a key area of ongoing research known as the coronal heating problem. First, let's get one thing out of the way. You ask: Or is there a type of matter with thermal conductive properties that could accomplish this? There can be no such material. Any material that passively diffuses heat from a cooler region to a warmer one ...

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In a comment engineer has suggested using radio frequency induction, and this seems an excellent idea. The technique is widely used, for example in plasma etching, and it's not especially high tech. There is a Wikipedia article that describes the technique, though this is a bit short on practical advice. A Google search returns lots of likely looking hits.

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Introduction Let us define the density of particles of species $s$ in a volume element, $d\mathbf{x} \ d\mathbf{v}$, at a fixed time, $t$, centered at (x, v) as the quantity $f_{s}(\mathbf{x},\mathbf{v},t)$. I assume this function is non-negative, contains a finite amount of matter, and it exists in the space of positive times and $\mathbb{R}^{3}$ and ...

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So I looked into this a little more and think I have an answer. If we assume a force-free situation, then we can write: $$\mathbf{J} \times \mathbf{B} = c_{o} \nabla \cdot \mathbb{P}$$ where $\mathbf{J}$ is the current density, $\mathbf{B}$ is the magnetic field vector, $c_{o}$ is some constant, and $\mathbb{P}$ is the pressure tensor. If we decompose ...

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Plasma can be created from many substances. More importantly, plasma can have the same density as liquids or solids, or even much more dense. One case widely-studied nowadays is the laser-produced plasma. By focusing an intense laser on matter, the electric field of the laser light can be so strong to ionize atoms very quickly (less than a femtosecond) thus ...

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In a plasma the particles are very hot. So hot that the atoms move so fast and collide so hard that they kick off electrons from each other and create ions. Molecules are hardly stable at these conditions. At these temperatures everything is no longer solid or liquid. So you can make plasma with everything like water, iron, tungsten, etc, but they will ...

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A plasma is, by its nature a gas - it has no structure and the constituent particles are not strongly bound to each other. Well, at least it's approximately a gas, and it's certainly not a liquid or a solid, but has been described as "the fourth state of matter" http://pluto.space.swri.edu/image/glossary/plasma.html But it's easy (or at least ...

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I had thought that if you placed two electrons in a vacuum that they would accelerate away from each other without limit. However after speaking to shminux I realised that although they accelerate forever they reach a limiting velocity which depends on their potential energy. So the particles in my sim will reach a limited v. Problem was v was too large ...

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In my experience (PhD student working on laser plasma interaction experiments) these PIC codes are pretty closely guarded by their creators. There are a few out there, for example OSIRIS, VORPAL, and TurboWave in addition to VLPL. Of these I think only VORPAL is commercially available (through Tech-X) and the others you would need to contact the groups ...

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actually, the fire does not conduct electricity, it simple ionises the air around it and the free electrons create a conducting path across the gap

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I am not an expert - but I have experience looking at these concepts. The geometry of the rods would be compared to the geometry of the plasma. There are probably some dimensionless ratios that would come out of any analysis. For example, the distance between the rods and the mean free path of the plasma. Lets look at the geometry of a pinch device: ...

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The conductivity of plasmas is very high, though not infinite. In a metal wire the applied voltage accelerates the conduction electrons, but the electrons collide with and scatter off the atoms that make up the crystal lattice of the metal. This transfers energy from the electrons to the metal and the metal heats up as a result. The energy lost as heat is ...

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The second theorem of König states that the kinetic energy in a reference frame $E_c$ is related to the kinetic energy relatively to the center of mass $E^*_c$ in the following way: $$E_c=E_c^*+\frac12Mv_G^2,$$ where $v_G$ is the velocity of the center of mass in the reference frame and $M$ is the total mass. To answer your question, remark that the energy ...

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